10x magnifying glass with inch and metric scales folds flat for compact storage. Uses a one-inch glass lens for distortion free viewing with inch and millimeter scales on the perimeter of a 1-inch square viewing area. Opens to 1.875" x 1.5" x 2.25" (4.76 x 3.8 x 5.7 cm), or folds down to just over half-inch high.